Technical Field
A fan beam output device that outputs a fan beam has been conventionally known by JP2000-356518A.
Description of Related Art
The fan beam output device includes a laser light source that emits laser light, a relay lens that changes the emitted laser light into parallel light flux, and a cylindrical lens that spreads the laser light of the parallel light flux to form a fan beam.
A survey system has been known by JP2005-214854A. In such a survey system, a fan beam output device is provided in a target device, a fan beam is output toward a survey instrument, and the fan beam is moved in a vertical direction for scanning, so as to direct a telescope of the survey instrument to a target.
In such a fan beam output device, a cylindrical lens is arranged between a polygon mirror and a relay lens (collimator lens).
The arrangement of the cylindrical lens increases the number of components of the fan beam device, and also requires a space.